I have a bunch of examples of fuel trucks not operating in a logical way (v 0.7.5c b455):
- in this one the fuel truck comes over and delivers fuel to a bunch excavators refilling many of them, but there are still a few more just nearby (<20 tiles away) with low fuel. after delivering, the truck has remaining fuel, and instead of driving over to the rest of the excs to refuel them, it drives all the way back to the fuel station and wait there until that exc with ~30% gets to 10%, upon which it drives all the way back. all of the rest of the excs within range of the fuel truck (12 tiles?) all got refueled (bug - fuel truck doesn't refill all excs.save)
- in this one the fuel truck drives over and refills nearly everyone, except the one that's out of fuel (bug - fuel truck doesn't refill all excs 2.save)
- very similar to the first one (it doesn't refuel the rest of the excs on the other side of the ore sorter) -- but in this case, if you wait about 10 seconds, another fuel truck will follow right behind him and refuel an exc that just got refueled by the previous truck (bug - fuel truck doesn't refill all excs 3.save)
few suggestions for improvements:
- let the fuel truck refuel as many excs as possible on the return home
- let the fuel refuel all of the excs (and maybe trucks?) assigned to the tower.
- allow fuel trucks to be able to fill diesel storage tanks in their spare time too